In general, KVM switches consist of two types of ports. CPU ports (interfaces to the servers to be controlled) and a local port. The local port allows communication links for keyboard, mouse and video data to be aggregated and controlled by local terminal devices having keyboard and mouse control devices and a video display. Local terminal devices are typically connected directly to the KVM switch and are intended to be used by administrative personnel to control the KVM switch, such as to switch to different CPU ports or to setup certain parameters such as security information. This is referred to as a “local user mode.”
The CPU ports provide access to the KVM switch and allow users to access networked workstations running WEB browsers with BIOS-level, and up, remote access, and control of up to 64 servers located anywhere in the world. This mode of operation is referred to as the “IP mode” or “remote user mode.”
Because local and remote users are accessing the KVM switch through different ports, an issue arises between the display seen by a user. More specifically, a remote user and a local user will experience different views when accessing the KVM data.
In inexpensive KVM switches with very limited functionality, local ports are typically accessed by users using special keystrokes or specific mouse movements but relay no visual feedback from the switch to the local user. Other systems such as those described in U.S. Pat. No. 5,721,842 issued to Beasley, use on-screen display technology (“OSD”) to provide information to a local user. Current OSD technology uses clunky fonts and does not have graphical pixel based capabilities that dramatically limit presentation capabilities. Reliance on the OSD technology is further constrained when the KVM switch provides remote network based access, i.e., KVM over IP to remote users and OSD access to local users.
Further, in addition to the difficulty of having to manage, learn or maintain multiple different systems, OSD technology is highly proprietary. Every piece of data or information has to be encoded using proprietary techniques. This doubles the effort for every change and every localization that needs to be done during the product life cycle because changes have to be adopted for the OSD view and for the web-based view. Further, the different user experiences and interface also leads to doubling the training and support efforts.
It is desirable to provide a KVM switch that utilizes the same display interface for both local and remote users. It is further desirable to provide KVM users with a KVM interface that utilizes similar instruction and control sets in both the remote and local modes.